6H9A:
reference: Structural and Mechanistic Basis for Anaerobic Ergothioneine Biosynthesis., Leisinger F, Burn R, Meury M, Lukat P, Seebeck FP, J Am Chem Soc. 2019 May 1;141(17):6906-6914. doi: 10.1021/jacs.8b12596. Epub 2019, Apr 23. PMID: 30943021

This OCA Structure page
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